Question: Is it possible to produce words from farts?
Short answer: No.
Long answer: In Kurt Vonnegut’s novel Breakfast of Champions, there is a story about an alien who communicates through farts. Unfortunately, no one understands him and he is killed while trying to explain how to cure cancer.
Given that farts do share some characteristics with vocal sounds, it seems possible that they could be used to communicate in some way. Indeed, herring fish communicate by farting.
Human vocal sounds are typically in the range of 100 Hz to about 8000 Hz, with the fundamental frequencies being in the range of about 100 to 250 Hz. This range is largely overlapping with that of fart sounds, particular those associated with greater smelliness. Thus, it is theoretically possible that very smelly farts could be modulated in frequency in such a way as to produce speech sounds. This kind of modulation would require exquisite control of fart frequency, and it’s not clear if that would be physiologically possible. Even the greatest flatulists in history had limited command of the sound frequency of their farts.
However, it turns out that sound frequencies are surprisingly unimportant for speech perception. What matters more is the sound envelope, which is the variation in sound amplitude over time. This fact suggested to us a possible way of encoding speech by modulating the rate at which air is released throughout the duration of a fart. We tested this idea by taking a fart sound from our database and modulating its volume by the envelope of a speech sound. The separation of sounds into frequencies and envelopes involves a relatively straightforward application of the Hilbert transform.
The example “carrier” fart can be heard here:
The waveform of this fart is shown in the middle plot below:
On the left is a waveform corresponding to a male voice saying, “Hello” .
On the right is the carrier fart modulated with the “Hello” envelope, which should produce a fart version of the word “hello”.
Unfortunately, this does not seem to work. Here is the resulting sound, which does not seem very different from the original fart:
Perhaps this will be the topic of future research. In the meantime, we have constructed the next best thing, which is a Morse code version of “hello”, using only farts: